The prior art is represented by a suspension device in a multi-process machine, according to Finnish patent FI 79927. The device works well in normal forest conditions. However, felling is increasingly moving to mountainous conditions. In such conditions, a multi-process machine should be able to operate as a machine capable of both felling and processing trees that have already been felled on a slope.
Particularly the processing of trees felled on lower slopes requires the suspension device to have a good ability to operate in the posterior position, in which the suspension device is in a position opposite to the felling position. For the suspension device to operate satisfactory, the suspension device must rotate through 160°, in difficult conditions even through 180°.
In multi-process machines according to the prior art, an insufficient length of stroke of the operating device and, on the other hand, a lack of available space, are problems that limit the rotation of the operating device of the multi-process machine. In addition, from the point of view of the operation of the multi-process machine, the dead centre of the operating device occurs in a disadvantageous point in the path of the multi-process machine, which is detrimental to the operation of the multi-process machine.